Liquid crystal display devices and other display devices have an image-forming mechanism including polarizing elements placed as essential components on both sides of a liquid crystal cell, and generally, polarizing films are attached as the polarizing elements. A pressure-sensitive adhesive is generally used to bond such polarizing films to a liquid crystal cell. When such polarizing films are bonded to a liquid crystal cell, a pressure-sensitive adhesive is generally used to bond the materials together so that optical loss can be reduced. In such a case, the pressure-sensitive adhesive is provided in advance as a pressure-sensitive adhesive layer on one side of a polarizing film, and the resulting pressure-sensitive adhesive layer-bearing polarizing film is generally used because it has some advantages such as no need for a drying process to fix the polarizing film. A release film is generally attached to the pressure-sensitive adhesive layer of the pressure-sensitive adhesive layer-bearing polarizing film.
When a liquid crystal display device is manufactured, the pressure-sensitive adhesive layer-bearing polarizing film is bonded to a liquid crystal cell. In this process, static electricity is generated when the release film is peeled off from the pressure-sensitive adhesive layer of the pressure-sensitive adhesive layer-bearing optical film. The static electricity generated in this manner may affect the orientation of the liquid crystal in the liquid crystal display device to cause a failure. The static electricity may also cause display unevenness when the liquid crystal display device operates. For example, the static generation can be suppressed when an antistatic layer is formed on the outer surface of the polarizing film. In this case, however, the effect is not high, and there is still a problem in that static generation cannot be fundamentally prevented. To suppress static generation in a fundamental position, therefore, the pressure-sensitive adhesive layer is required to have an antistatic function. Concerning means for providing an antistatic function to a pressure-sensitive adhesive layer, for example, it is proposed that an ionic compound should be added to a pressure-sensitive adhesive used to form a pressure-sensitive adhesive layer (Patent Documents 1 to 6).